title: Evaluation of calcium loss after transcatheter aortic valve implantation.
abstract: OBJECTIVE
  Aortic valve calcification and changes after transcatheter aortic valve implantation (TAVI) were specifically assessed by computed tomography (CT). The main difference between TAVI and the conventional technique is the compression of the cusps of the calcified native valve against the aortic wall before implantation. The objective of this study was to quantify the segmented calcification in the area of the basal annular plane before and after TAVI.
  
  
  METHODS
  The CT scans of 20 patients (13 male and 7 female; mean age: 82.9 ± 8.1 years) were assessed. The aortic valve calcification was segmented; derived from this segmentation volume, mass and Hounsfield units (HU)/density of the calcifications on the annulus and cusps before and after TAVI were evaluated. Pre- and postoperative data were compared regarding potential calcification loss and calcification distances to the left and right coronary ostia.
  
  
  RESULTS
  Significantly lower postprocedural mean volumes and masses for all cusps (P < 0.001) were found. The mean differences in the volume for the non-coronary, right-coronary and left-coronary cusp were -156.8 ± 53.73, -155.5 ± 62.54 and -115 ± 57.53 mm(3), respectively, and differences in mass were -88.78 ± 29.48, -95.2 ± 39.27 and -71.56 ± 35.62 mg, respectively. Over all cusps, mean HU increased after intervention [784.41 ± 92.5 HU (pre) and 818.63 ± 78.71 HU (post); P < 0.004]. In 80.03% of all cusps, calcification loss was found; all patients were affected. Significantly lower (P < 0.047) postprocedural mean distances were found from the left and right coronary ostia to the next calcification point.
  
  
  CONCLUSIONS
  Our results show a significant loss of calcification in all patients after TAVI, with a reduction in the calcification distances to the coronary ostia and the compression of calcification in the area of the device landing zone. The clinical implications of this finding need to be investigated further.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Switzerland.
authors.forename: Thi Dan Linh
authors.initials: TD
authors.lastname: Nguyen-Kim
authors.forename: Ayhan
authors.initials: A
authors.lastname: Sahin
authors.forename: Simon H
authors.initials: SH
authors.lastname: Sündermann
authors.forename: Anna
authors.initials: A
authors.lastname: Winklehner
authors.forename: Jürg
authors.initials: J
authors.lastname: Grünenfelder
authors.forename: Maximilian Y
authors.initials: MY
authors.lastname: Emmert
authors.forename: Willibald
authors.initials: W
authors.lastname: Maier
authors.forename: Lukas
authors.initials: L
authors.lastname: Altwegg
authors.forename: Thomas
authors.initials: T
authors.lastname: Frauenfelder
authors.forename: Volkmar
authors.initials: V
authors.lastname: Falk
authors.forename: André
authors.initials: A
authors.lastname: Plass
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging / Q000378:metabolism / Q000628:therapy*; D002114:Calcinosis / Q000000981:diagnostic imaging / Q000378:metabolism / Q000628:therapy*; D002118:Calcium / Q000378:metabolism*; D006328:Cardiac Catheterization; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D061330:Multidetector Computed Tomography; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D002118:Calcium
keywords: Aortic root; Aortic valve repair; Aortic valve replacement; Valve calcification